you look at 84 attacks coming out of those groups compared to four from al qaeda, how do you they are apples and oranges except for the fact that they fit our inclusion criteria. a lot of terrorism and the united states is born and raised here. host: based on your background in this, are there any parallels to what happened in the oklahoma city bombing, to what we potentially could see with the 19-year-old dzhokhar tsarnaev, who is about to be charged probably later this week? guest: it certainly well within the cards. if he is convicted, what will be the fifth largest act of terrorism in the united states, then went on to be involved in the murder of another law enforcement official, and then went on to throw improvised explosive devices out of two cars, one of which was a carjacked vehicle. this is an extraordinary example of violence. depending on evidence, which i certainly have no inside knowledge of, this has the potential to go to trial. host: one day after the bombings took place, the other was killed in that shooting in watertown, massachusetts, the center public and later mitch mcc